At the same time, the question is how much will this deal change the political calculations in the Middle East?
The answer is, not much. In trying to get Iran on the table, Obama had to upset the regional power brokers, notably Saudi Arabia.
Granted, it is doubtful that the Saudis (and Israel) are going to be happy of any deal short of complete surrender by Iran. Yet, they might be far more willing to entertain even a bad deal with Iran if they trusted that Obama knew what he was doing or at least was more sensitive to their concerns.Events in the past several days has shown that the Saudis do not trust Obama's moves in the Middle East. They believe the United States was far too eager for a quick nuclear deal with Iran. As Rothkopf noted:

The administration’s good first-term toughness toward Iran on nuclear sanctions was followed by a second-term hunger for a nuclear deal that was so great that everyone from Tehran to Toledo, Ohio, now believes that the United States wants the deal more than the Iranians do and has lost negotiating leverage as a result.

It is telling when Saudi Arabia didn't bother to warn the United States of their sudden and unexpected invasion of Yemen, which caught the Obama Administration off-guard. The Saudis didn't inform the US because they didn't trust Obama, afraid that Washington would leak the news to Iran.

More importantly, the Saudis no longer care what the United States thinks, as Mustafa Alani, director of the national security and terrorism studies department at the Gulf Research Center, argued:

We see the beginning of a new policy, where [Saudi] interest is basically more important than U.S. objections or with Security Council resolutions.... Basically, we are adopting the Iranian style and the Israeli style: When it comes to your national interest, you go ahead and do it.

Not surprisingly, Senator John McCain thundered that this development "signals a reality that the countries in the region no longer have confidence or are willing to work with the United States of America." In the meantime, David Rothkopf bluntly stated that Obama's policy in the Middle East was an egregious failure, a giant cluster-fuck. In essence, Obama's victory lap is very premature. Should Iran decide to renege even a bit on the still tentative deal before its signing later this year, it will not, for sure, boost the Saudis's confidence on this administration.